Tensioning device



' Eaten 2 SHEETS- SHEET l..

W nn!!! g 9 .9 I ,1 a a 9 0 O T 6 0 o l L ted May 2, 1922.

. ing.

CHARLES F. PEASE, OF CHICAGO, ILLINOIS,

ASSIGNOR To THE 0. n. :eiiAsE COMPANY,

, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

rnusroivrne DEVICE.

To all whom itmay concern:

Be it known that I, CHARLES F. PEAsn, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certainnew and useful Improvements in Tensioning Devices, of which the following is a specification.

This invention relates to tensioning devices, and it comprises the combination with a shaft or roll, of an adjusting shaft, hearing brackets for said first mentioned shaft loosely mounted on said adjusting'shaft, a crank or handle secured to said bearing brackets, a lever loosely mounted on said adjusting shaft, a spring secured to said lever, and means for retaining said handle and said lever in adjusted posltio-n.

In the present invention, I have provided a tensioning device suitable for general application, and particularly applicable for use in connection with the endless band employed on blue printing machines, for the purpose of maintaining proper tension on the band and preventing creasing. In-machines of this character, the band passes beneath a. glass bed or plate over spaced rollers. The roller at one end of the shaft is made adjustable to secure proper tensioning.

To secure proper adjustment of the movable roller, I provide an adjusting shaft having a pair of bearing brackets loosely mounted thereon, said bearing brackets beadapted to support the movable roller and being provided with a crank. or'extension by means of which the roller may be ad.- j usted. A lever is also loosely mounted on the adjusting shaft, and a spring is connected to the lever to maintain the lever under proper tension. The crank and lever may be connected to each other by any suitable means.

'In the accompanying drawings, I have shown one embodiment of the invention. In this showing:

Figure 1 is a front elevation of a blue printing machine showing the invention applied,

Figure 2 is a side elevation, and,

Figure 3 is a detail view of theendless band, detached, showing the adjusting mechanism.

Referring to the drawings, the reference numeral 1 designates a suitable base havlng legs 2, by means of which the machine is supported. A platform or table 3 1s ar- Specification of Letters Patent.

Patented Ma 2, 1922.

Application fiIed February Y, 1921. Serial No. 443,042.

.ranged at the top of the front legs, the rear legs extending upwardly to form asupport for the printing mechanism. A motor 4: is arranged on the base and is adapted to drive a vertical shaft 5, by means of which theendless band is driven. A horizontal shaft 6 is arranged at the top of the machine, and

this shaft'is driven from the vertical shaft by. means of bevel gears 7 and 8, mounted on the shafts 5 and 6 respectively, and meshmg with each other. Arc lamps 9 are arranged over the platformor table 3, in the usual manner. A cradle or bed 11 is arranged adjacent the arc lamps and a plate 12 of glass or other transparent material is arranged therein. Theplate is adjustable in'the cradle by means of bolts 18.

The upper band roll 14 is mounted on horizontal shaft 6, and the endless band or belt 15 passes over this roll. An idler roll 16 is arranged on a shaft 17, supportedin suitable bearings, secured to the frame of the machine. The lower movable roll 19 is supported on a shaft 20, secured to bearing brackets 21. These brackets 21 are provided with hubs 22, surrounding the adjusting shaft 23, mounted in suitable bearings on the frame of the machine. One of the hearing brackets is provided with a crank or. handle 24, secured thereto and arranged at an angle to the bracket (see Figure 3). A lever 25 is loosely mounted on the adjusting shaft 23 and a spring 26 is secured to the free end of the lever. The end of the spring may be secured to the frame of the machine at any suitable point.

The crank or handle 24: is provided with an extension 27. having an. arcuate slot 28. A bolt 29 is carried by the lever 25, and is adapted to be received in said slot, whereby the handle and bearing brackets may be maintained in any adjusted position under tension exerted by spring 26. The foot treadle 30 is pivotally mounted on the frame of the machine, and is secured to the lever 25 by means of links 31.

In operation, the band or belt is applied to the machine and the glass is properly adjusted to prevent creasing of the band. When the band is applied to a machine, if the contact glass is not properly adjusted, creasing in the center of the band will occur when it is placed under tension. The band may be placed under any desired tension and the spring 26 elongated by adjusting the position of roll 19. When the roll is moved downwardly, to place the band under tension, andbolt 29 tightened, to'secur'e to be'talren as a preferredexample, of the same, andthat various changes in. the shape,

the lever With respect to the handle 24;, tension is placed on spring 26. The proper tension having been obtained, the band may "be adjusted from time to time as it stretches, by loosening nut 29 and forcing the handle- 24 closer to the lever 25. .i

1 To temporarily relieve the tension, the foot treadle 30 is depressed, moving the lever 25 forwardly and thus moving the roller 19 toward the roller 14 and loosening the tensionv on the bolt. 7 c

7 It is to be understood that the form of my invention herewith shown and described 7 is means for securing said lever and said bracket to each other, said means being capable of adjustment, and a spring secured to the free end of said lever.

2. i The combination With an endless band, of a pair of rolls, one of said rolls being adjustable, and tensioning mea ns therefor, said means comprising bearing brackets adapted to" receive said adjustable roll, a handle secured to one of said brackets, a freely mounted lever, a spring secured thereto, and means for securing said handle to said lever.

3. The combination Wltllfll'l endless band, of a pair of rolls, one of said rolls being adjustable, and tensioning means therefor,

said means. comprising bearing brackets adapted to receive "said adjustable roll, a

handle secured to one ofsaid bearing brackets, an extensionformed on said handle, said extension being provided with an arcuate slot, a freely mounted lever, a spring secured thereto, and fastening means arranged insaid slot and secured'to said lever. v

of-a pair of rolls, one of" said rolls being adjustable, and tensioning means therefor,

a. Thecombination with an endless band,

saidmeans comprising an adjusting shaft arranged adjacent said adjustable roll, a pair of bearing bracketsfreely mounted on said shaft and supporting'said r011 a, handle secured to one of said brackets, an extension formed on said handle, said extension being provided with an arcuate slot, a lever freely mounted on said ad usting shaft, a spring se-' cured to said lever, andfastening means arranged in said slot and engaging said leverv In testimony Whereof'l aiiix mysignature in presence of tWO'WltHeSSeS. v

CHARLES RPEASE.

Witnesses: j r 7' GRAGEWALKINSHAW, I A. M. DQDDERER. 

